Animating data that enters and leaves the plot area

I have an animated “bar” chart where the order of the bars changes in response to some slider controls. I am only showing the top 20 bars out of 120 currently, and I found the animation is smoother when I plot all 120 bars, even though most of them are not visible (so that if they become visible they smoothly transition into the plot area).

The bars are actually rendered as scatter traces with mode=“line+text” (the bars are annotated with text that is also animated).

I want to know how plotly handles data that is outside the plot area. Does it slow plotly down much? I may have to increase the total number of bars to 25000 and I am worried it will slow to a crawl. Do I need to remove old frames from the animations to avoid excessive memory usage?

I am working through the R API.